How Lithium-Ion Batteries are Paving a Way for a Rechargeable Future
Recently, there have been innumerable talks regarding the recharging potential of the energy sector and the automobile market. While many companies are already testing the power of batteries in keeping our vehicles running, India, in 2019 launched their first grid-scale storage project, with a 10MW Li-ion system powering it. This project has been described of strategic importance for India’s entire energy sector and it’s the first grid-scale lithium-ion battery energy system that went into service from February 2019.
It was hard to not reflect on the domineering potential of the lithium-ion batteries after the 2019 Nobel Prize was handed down to John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino for their efforts and researches in the field of lithium-ion batteries. The Swedish Academy of Nobel Prize was very specific after handing down the Nobel Prize, they helped in creating a rechargeable world.
It is true, lithium-ion batteries have changed the way we use electronics since 1991 when they were launched first in the market. The story of lithium-ion batteries goes like that, Stanley Whittingham laid the foundation of lithium-ion battery during the oil crisis, in 1970. John Goodenough innovated the battery’s cathode in 1980. And, Akira Yoshino made the first commercially viable lithium-ion battery in 1985.
So, What is a Lithium-Ion Battery, and What are its Advantages?
Well, lithium-ion batteries are much different than the AA or AAA rechargeable batteries and much better than its predecessor, the lead-acid battery. They can charge easily at high rates and are the most versatile batteries in the market. Its rapidly changing power reduces its downtime as well. The high discharge rate is the perfect power you need for your devices. Lithium-ion batteries are not affected by temperature fluctuations, unlike its predecessor lead-acid battery. Furthermore, lead-acid batteries needed regular water replacement to avoid structural damages, otherwise, it shortened the lifespan of the battery if not maintained properly. The lithium-ion batteries come with a powerful energy storage density, which is their best aspect. With solar charging enabled lithium-ion batteries in the market, they can use renewable power to drive forth robust energy storage.
The Architecture of Normal Batteries
Any normal battery consists of an anode and a cathode. Both of these components are made of metals and have different chemical potentials. An electron flow occurs from the anode to the cathode which produces chemical energy. The electrolyte, which is a conducting fluid, is used to transfer the electrons inside the battery. In single-use batteries this chemical reaction that produces the electrons cannot be reversed, however, in rechargeable batteries, it can be. Every AAA or AA rechargeable battery comes with recharge cycles that define how many times this chemical reaction can be reversed, after which, they are rendered useless for further use. Unlike single-use batteries, these are environmental-friendly and can power your devices for a very long time.
The Chemistry of Lithium-ion Batteries
Unlike the normal batteries, lithium-ion batteries do not depend on chemical reactions happening from cathode to anode. However, they do depend on the flow of lithium-ions back and forth between the anodes to cathode. The first lithium-ion battery tested by Whittingham involved cathode constructed from titanium disulfide and anode from metallic lithium. One drawback of this battery was its high reactivity of the metallic lithium that made it highly vulnerable to fire and explosion. Goodenough tweaked the model by constructing cathode with transition metal like Cobalt or Nickel. This change significantly improved the performance of the battery. The first commercial lithium-ion battery, constructed by Akira Yoshino involved anodes made from petroleum coke, instead of reactive metallic lithium.
The Electrolytes Used for Lithium-Ion Batteries
The most popular electrolyte for lithium-ion batteries is Lithium Hexafluorophosphate (LiPF6) along with a mixture of carbonate solvents. The carbonates used included, dimethyl carbonate, ethyl methyl carbonate, or diethyl carbonate. This kept the viscosity of the electrolyte low and its conductivity high. However, they had flashpoints close to the room temperature and this made them highly volatile and flammable.
Exploring the Alternative to Hazardous Electrolyte
There have been many types of research exploring the possibility of replacing the electrolyte for something that called as solid electrolytes. Unfortunately, the low mobility of lithium ions limited its performance in terms of charge and discharge rates. A breakthrough was achieved by Universite Catholique de Louvain, Belgium with its new compound called LiTi or LTPS. This could enhance the mobility of the lithium-ions and had the highest diffusion coefficient ever measured in a solid. The discovery of LTPS has opened several avenues for similar materials that have a better lithium diffusion coefficient, paving way for a rechargeable future.
Wrapping it Up
The catastrophic effects of climate change have created a need to accelerate the adoption of renewable energy options that are safer and reliable. With wind and solar energy being tested to diminish dependency on fossil fuels, we need bigger and more powerful batteries to achieve that dream. A robust battery like lithium-ion batteries is the key to a smooth and rapid transition to rechargeable and environmental-friendly future.